In a typical computer, an operating system executing on the computer maintains an overall file system. This overall file system provides the infrastructure needed to enable items, such as directories and files, to be created, stored, and accessed in an organized manner.
In addition to having directories and files, the overall file system may also comprise one or more mounts. These mounts enable devices, other file systems, and other entities to be “mounted” onto particular mount points of the overall file system to enable them to be accessed in the same manner as directories and files. For example, a floppy disk drive, a hard drive, a CDROM drive, etc., may be mounted onto a particular mount point of the overall file system. Similarly, a file system such as a process file system (ProcFS) or a network file system (NFS) may be mounted onto a particular mount point of the overall file system. Once mounted, these entities (referred to herein as “mounted entities”) may be accessed in the same manner (from the standpoint of a user) as any other directory or file. Thus, they are in effect incorporated into the overall file system.
The mounted entities may be accessed by processes running on the computer. To access a mounted entity, a process may submit a request to the operating system for a list of all of the mounts in the overall file system. When the operating system returns the requested list, the process may select one of the mounts, and submit a request to the operating system to access the mounted entity on that mount. Barring some problem or error, the operating system will grant the request; thus, the process is able to access the mounted entity. Such an access mechanism works well when all processes are allowed to have knowledge of and hence, access to, all mounts in the overall file system. In some implementations, however, it may not be desirable to allow all processes to have knowledge of, and access to, all mounts. In such implementations, the above access mechanism cannot be used effectively.